Interventions designed to improve financial capability: A systematic review

Abstract Background There is growing recognition that people need stronger financial capability to avoid and recover from financial difficulties and poverty. Researchers are testing financial capability interventions with adults, children, immigrant populations and other groups, but little is known about the effectiveness of financial capability interventions on financial behaviour and financial outcomes. Objectives The purpose of this review is to inform practice and policy by examining and synthesizing evidence of the effects of interventions designed to improve financial capability. Financial capability interventions combine financial education and financial products and/or services. The research questions are: (a) What are the effects of interventions designed to improve financial capability on financial behaviour and financial outcomes? and (b) Does study(design), intervention (dosage, duration, type) or sample (age) characteristics relate to the magnitude of effect size? Methods We conducted two identical rounds of electronic searches for two different time periods. In Round 1 searched for studies through May, 2017 and Round 2 searched from May, 2017 through May, 2020. For both rounds, we identified and retrieved both published and unpublished studies, including conference proceedings, through a comprehensive search that included multiple electronic databases, grey literature sources, organizational websites, government websites and reference lists of reviews and relevant studies. We also conducted forward citation searching using Google Scholar to search for studies citing the included studies. We also conducted a search on Google using key terms. We hand searched the table of contents of selected journals to identify potentially eligible reports not properly indexed. Finally, experts who were study or sub‐study authors of prior studies were contacted in an attempt to obtain unpublished studies, studies in process and published studies missed in the database search. Selection Criteria To be eligible for this review, the intervention must have included a financial education component and a financial product or service. Studies must have also been conducted in any of the 35‐member countries of the OECD, and included a financial behaviour or financial outcome. To meet the criteria for delivering financial education, interventions must have delivered information about: (1) a variety of general financial concepts and behaviours, or advice about financial behaviours); (2) a specific financial topic; (3) a specific product; and/or (4) a specific service. To meet the criteria for access to a financial product or service, interventions must have facilitated access to one or more of the following: (1) a child development account; (2) a retirement account through an employer; (3) a ‘second chance’ checking account; (4) a matched savings account; (5) a financial service, such as financial counselling or coaching; (6) a bank account; (7) an investment vehicle; or (8) a home mortgage loan product. Data Collection and Analysis Electronic searches of bibliographic databases and searches of other sources identified a total of 35,484 hits. Titles and abstracts were screened for relevance and 35,071 were excluded as duplicates or deemed inappropriate. The full text of the remaining 416 potential studies was reviewed and screened for eligibility by two independent coders. We excluded 353 reports that were deemed ineligible and included 63 reports that met inclusion criteria. Of the 63, 15 reports were deemed duplicates or summary reports. Of the remaining 48 reports, 24 were unique studies (using unique samples) that were included in this review. Six of those 24 studies were large longitudinal studies that presented unique analyses (using different time points, subsamples, and/or outcomes). Thus, we extracted data from 48 reports, reporting data and analyses from 24 unique studies. At least two review authors who were not study authors independently assessed risk of bias in all included studies using the Cochrane Collaboration's risk of bias tool. Results The review summarizes evidence from 63 reports from 24 unique studies, which included 17 randomized controlled trials and 7 quasi‐experimental designs. In addition, 17 duplicate or summary reports were also located. This review identified several different types of previously evaluated financial capability interventions. Unfortunately, few interventions that were evaluated by more than one study measured the same or similar outcomes, thus there were not a sufficient number of studies of any of the included intervention types that could be pooled to conduct a meta‐analysis. Therefore, evidence is sparse about whether participants’ financial behaviours and/or financial outcomes are improved. While the majority of the studies used random assignment (72%), many of the studies had some important methodological weakness. Authors’ Conclusions There is a lack of strong evidence about the effectiveness of financial capability intervention. Better evidence is needed about the effectiveness of financial capability interventions to guide practitioners.

1 | PLAIN LANGUAGE SUMMARY 1.1 | Little rigorous evidence on interventions combining financial education with financial products and services from mainstream financial institutions There is no clear evidence that financial capability interventions, which include financial education linked to a mainstream financial product or service, improve financial behaviours or financial outcomes.

| What is this review about?
The growth in individual responsibility for one's finances dovetailing with the growth in financial products and services, including those in the alternative financial services sector, has resulted in higher financial risk. People need stronger financial capability to avoid and recover from financial difficulties.
Financial capability, or the ability to use knowledge to demonstrate desirable behaviours towards financial well-being, requires knowledge, access and ability to use a financial product or service. This systematic review assesses the state of research on interventions that combined financial education and a mainstream financial product or service ('financial capability interventions'). It examines the financial behaviours and financial intervention outcomes.
What is the aim of this review?
This Campbell systematic review examines the effects of interventions that combine financial education and mainstream financial products and services. The review summarizes evidence from 63 reports from 24 unique studies.
1.3 | What are the main findings of this review?

| What studies are included?
For this review, the intervention must include financial education and a financial product or service. Studies that described interventions that provided only financial education, or financial education services (e.g., mentoring), or only facilitated financial access, were excluded.
This review includes studies that evaluate the effects of financial capability interventions compared to a group that received nothing, treatment as usual, or different treatment. A total of 63 reports were identified, with another 17 duplicate/summary reports. Therefore, 48 reports of 24 unique studies were included.
Six of the 24 are large longitudinal studies that are reported on in 28 sub-studies that use various time points post-treatment and/or examined different outcomes from the same or different samples.
The studies spanned the years 2004-2020 and were all conducted in the USA. The majority of the studies were randomized control trials.

| What are the main findings of this review?
Financial capability interventions include financial education and access to a financial product or service from a mainstream financial institution.
Data were collected on financial behaviour and financial outcomes of the study participants using unstandardized instruments and included self-reported and administrative data.
Behaviour changes included bank or retirement account opening, asset purchase, savings rate, budgeting and retirement savings rate.
Financial outcomes included savings amount, credit score, debt amount, asset value and retirement savings amount.
This review identifies several types of previously evaluated financial capability interventions. Few interventions that were evaluated by more than one study measured the same or similar outcomes, thus there was an insufficient number of studies of any of the included intervention types that could be pooled to conduct a meta-analysis. Therefore, evidence is sparse about whether participants' financial behaviours and/or financial outcomes are improved.
Many studies had important methodological weakness, and a high or unclear risk of bias.

| What do the findings of this review mean?
There is a lack of strong evidence about the effectiveness of financial capability interventions. Better evidence is needed about the effectiveness of financial capability interventions to guide practitioners.
Policy actors that seek to facilitate increased financial capability through the interventions included in this review need a stronger evidence foundation.
Additional research on financial capability interventions using protocols, strong and transparent methodology, manualised interventions, common outcomes and more complete reporting is needed.

| How up-to-date is this review?
The review authors searched for studies up to May 2020.

| BACKGROUND
global financial crisis and subsequent growth in income and wealth inequality to levels unprecedented in recent US history, there is growing recognition that people need stronger financial capability to avoid and recover from financial difficulties and poverty (Miller et al., 2014;Mitchell & Lusardi, 2015).

| The intervention
There is growing academic and public policy interest in helping people gain financial capability. Researchers are testing financial capability interventions with adults, children, immigrant populations, and other groups (Batty et al., 2015;Curley & Robertson, 2017;Huang et al., 2013;Theodos et al., 2015). These interventions use various methods to increase financial education combined with financial products and services. The interventions differ in their methods of financial education and financial products and services, and their method for combining them, but they share this coordinated combination. For example, interventions to help parents learn to save money include financial education and access to a college savings account for their child (Huang et al., 2013). Policymakers are showing increased interest in these interventions, and implementing new policies designed to increase financial capability. For example, the states of Maine and Nevada have started state-wide financial capability and asset building programs . Countries are creating national strategies on financial capability, such as the countries within the United Kingdom, which set out a clear description of the problem and define clear goals for specific populations and geographic areas (Bagwell et al., 2014;Kempson, 2009). As outcomes, studies measure financial behaviours, such as setting aside savings as emergency or short-term savings (Azurdia & Freedman, 2016;Collins & Urban, 2015;Huang et al., 2013;Skimmyhorn, 2012;Theodos et al., 2015), engaging in financial management (e.g., keeping records of expenses and income, paying bills on time, and using a budget) (Theodos et al., 2015), improving credit (Birkenmaier et al., 2014a;Theodos et al., 2015), participating in retirement savings plan (Duflo et al., 2006) and saving for an asset, such as children's college education (Han et al., 2009;Huang et al., 2013;Sherraden et al., 2011). Some researchers have also studied financial knowledge (Azurdia & Freedman, 2016;Han et al., 2009;Theodos et al., 2015) and financial mind-set (i.e., attitudes, motivation, and decision-making) (Skimmyhorn, 2012;Theodos et al., 2015). These outcomes all have the potential to impact a person's financial behaviours, which in turn impacts financial well-being, or the ability of a household to 'fully meet current and ongoing financial obligations, …feel secure in their financial future, and…make choices that allow them to enjoy life' (Consumer Financial Protection Bureau [CFPB], 2015). Other financial interventions also combine financial education and financial products or services and are considered in this review. These interventions may be known as financial counselling and coaching, and combine financial education and access to financial products and services. Financial mentoring and financial therapy are interventions that do not routinely combine these two, and are excluded from this study.

| How the intervention might work
There is a growing awareness that financial knowledge, while necessary for optimal financial choices and behaviours, is insufficient by itself in today's world (Austin & Arnott-Hill, 2014;Fernandes et al., 2014;Hastings et al., 2013;Miller et al., 2014;Mitchell & Lusardi, 2015). Results of meta-analysis studies focused on financial education efforts alone suggest that by itself, financial education has weak effects on financial behaviour (Fernandes et al., 2014;Kaiser & Menkhoff, 2019;Miller et al., 2014). Fernandes et al. (2014) found that interventions to improve financial knowledge and skills explain only 0.1% of the variance in financial behaviours studied, with weaker effects in low-income samples. A second meta-analysis found that the impacts of financial education are highly heterogeneous (Kaiser & Menkhoff, 2016). Miller (2014) found that the combination of financial knowledge and skills has a positive impact on some behaviours and outcomes (savings, financial skills), but not in all studied (debt repayment), and had no significant overall effect size findings. Kaiser and Menkhoff (2019) found that financial education delivered in schools for children and youth had an effect of 0.07 standard deviation units on financial behaviours.
Thus, while financial education may lead to financial knowledge, the relationship between knowledge and behaviour appears weak.
However, research suggests that access to financial products and services from mainstream financial institutions (e.g., bank accounts and retirement accounts) is significantly associated with financial behaviour (Birkenmaier & Fu, 2020), and financial behaviour is associated with financial well-being indirectly through its relationship with one's objective financial situation. In other words, access to financial products and services is associated with financial behaviour, and financial behaviour may impact the objective financial situation, which may in turn impact financial well-being (Walker et al., 2018).
Rather than focusing solely on financial education or on financial products and services, a focus on the combination of financial knowledge and skills, and access to appropriate financial products and services (Sherraden, 2013), or financial capability, has demonstrated promise to result in financial behaviours and outcomes that facilitate financial well-being (Collins & Urban, 2015;Curley & Robertson, 2017;Huang et al., 2013;Theodos et al., 2015). This combination is grounded in Sen (1999) and Nussbaum's (2007) theoretical work on capability, which postulates that people's choices reflect both their knowledge and their real opportunities within their lived environment. Capability incorporates people's internal capabilities (abilities, knowledge, and skills) with external capabilities (e.g., the range of opportunities available through products, services, and institutions).
Internal and external capabilities interact to further develop one's internal capabilities (Nussbaum, 2011, p. 21). Applying these concepts to financial capability means focusing on the financial decisions people make based on their innate ability, knowledge, skills, as well as the opportunities afforded them through their environment. Their innate ability to demonstrate financial behaviours is a result of the interaction of their internal and external capabilities, and growth of their internal capability through such interaction (Sherraden, 2013).
To improve one's financial behaviours, a focus on both internal capabilities through financial education and external capabilities through the financial products and services available to them is needed. As shown in Figure 1, the financial capability framework recognizes that both financial education and financial products and services are determinants of an individual's financial behaviours, and that the interaction of the two allows individuals to apply their knowledge and skills through their financial behaviours, such as the degree to which they save money for emergencies or retirement, pay bills on time, and invest in assets that appreciate in value (Huang et al., 2014;Peeters et al., 2018). The interventions that use both elements also utilize important elements identified by the World Bank as essential to better financial interventions. By combining knowledge and financial products and services, interventions are 'targeted and relevant', provided at a 'teachable moment' when the participant might apply the information in a real-world setting presently or in the near future, and 'give exposure to information over the longer-term' through the use of a product or service (Lundberg & Mulaj, 2014).
Interventions designed to increase financial capability are diverse, yet designed to both strengthen financial knowledge and access to appropriate financial products to impact behaviour. Financial knowledge interventions involve a diverse range of types, goals, and delivery models. Some financial knowledge interventions utilize a set curriculum (Birkenmaier et al., 2014a), while others are tailored to the client's situation (Huang et al., 2013), expressed goals and interest areas (Theodos et al., 2015), or are specific to a financial product or service (Azurdia & Freedman, 2016;Collins & Urban, 2015). Financial knowledge interventions may have the goal of increasing general financial knowledge (Han et al., 2009), financial knowledge specifically related to a particular client situation (Theodos et al., 2015), or financial knowledge about a particular type of product or service (Azurdia & Freedman, 2016;Collins & Urban, 2015). Delivery models include one-on-one financial education (Azurdia & Freedman, 2016;Theodos et al., 2015) online financial education (Collins & Urban, 2015), and classroom-based financial education (Birkenmaier et al., 2014a). In interventions designed to improve financial capability, these financial knowledge elements are paired with a financial product or service element, such as debt or credit interventions for a particular client situation (Theodos et al., 2015), a child education savings account (Huang et al., 2013), savings and checking accounts at banks and credit unions (Birkenmaier et al., 2014a), retirement saving plans (Collins & Urban, 2015), matched savings accounts for asset development (Han et al., 2009), or emergency savings accounts (Azurdia & Freeman, 2016), among others. The range of financial capability behaviours impacted includes savings, investment, record keeping, and loan repayment behaviours (Miller et al., 2014).
An important difference among interventions, however, is whether the intervention includes only financial education, or whether financial education is linked to financial products and services onto which participants can act to better their financial situation with their newfound knowledge. Interventions that include only financial education and are not designed to increase participant access to appropriate financial products and services that allow them to act on their knowledge assume that knowledge alone can result in financial behaviour change. Indeed, prior reviews have found that financial education alone has weak effects on behaviour (Fernandes et al., 2014;Kaiser & Menkhoff, 2019).
Financial capability interventions to be included in this review combine financial education and financial products and services and thus capitalize on the interaction of the two elements to affect financial behaviour. Some of the interventions are created for onetime studies, while others are incorporated into long-term programs that are supported through government and/or private funding. The interventions reported on in this review that are part of large programs are the following: a. Individual development accounts (IDAs). IDAs are special matched savings accounts designed to reduce poverty for adults. IDA programs, available across the US, require small, regular participant savings over time, and completion of financial education. Account proceeds, plus a matched amount from public or private funds, can be used to start a small business, pay for postsecondary education or purchase a home. Starting in the late 1990s, US federal funding was available from the Assets for Independence Act (AFIA), but federal funding was discontinued in 2017. Since then, individual US states and private funding has been supporting the programs (Center for Social Development, d. Employer-provided retirement accounts. Employer-provided retirement funds are generally one of two types: a defined benefit plan (i.e., a pension) that provides a specific monthly benefit for life; or a defined contribution plan, that provides a vehicle for employees and employers (or both) to contribute to an account an amount indexed to an annual salary. Federal tax benefits through the Internal Revenue Service are provided to employers who provide retirement benefits to their employees (Internal Revenue Service, 2020). e. Financial counselling and coaching. Financial counselling and coaching is provided by a wide variety of public, private and government sources without specific government sanction or regulation. Financial counselling provides tailored financial education and advice, while coaching provides tailored goal-setting and motivation, along with education (CFPB, n.d.). While distinct from each other, often in practice, there is also overlap. Interventions often partner financial counselling and/or coaching with other components, such as homeownership education and counselling and IDAs.

| Prior reviews
While several prior reviews discussed next contribute to our understanding of financial capability interventions, they have limitations.
Only four prior reviews have been conducted on interventions intended to improve at least one aspect of financial capability.
Fernandes and colleagues (2014) examined effects of financial literacy and financial education interventions on financial behaviours. Although the review methods were not clearly reported and the inclusion criteria were not well defined, the authors appear to have included 168 studies (published and unpublished), with 90 of those being studies that manipulated financial literacy with some education intervention and the remaining being studies that measured financial literacy (correlational studies). Fifteen of the 90 intervention studies used a randomized design, and the others used a quasi-experimental or pre-post design. They found that financial education interventions had weak effects on financial behaviour, especially in low-income samples. They found that financial literacy explains only 0.1% of the variance in financial behaviours studied, with weaker effects in low-income samples.
Miller and colleagues (2014) took a seemingly broader approach to their review, including any intervention that would impact financial knowledge, attitudes, and/or behaviours. They identified 188 studies via their search of one electronic database (Econlit), prior literature reviews, studies completed within the World Bank, and websites likely to include relevant studies. However, the authors reported that, 'to reduce the number of studies to a manageable size…only articles from peer reviewed journals were included from Econlit, for the period January 2009 to September 2013' (p. 7). Despite their seemingly broader inclusion criteria related to the interventions of interest, their meta-analyses reported on outcomes of financial education interventions from a small number of studies on the following outcomes: savings behaviour (n = 6), retirement savings (n = 5), loan defaults (n = 4), and record keeping (n = 5). Findings indicate that financial education interventions had a positive and statistically significant mean effect on retirement savings (effect size [ES] = 0.08; 95% confidence interval [CI], 0.01, 0.16), but a null or negative and non-statistically significant mean effect on savings (ES = 0.03; 95% CI, 0.00, 0.06), record keeping (ES = 0.04; 95% CI, 0.00, 0.09) and loan default (ES = −0.02; 95% CI, −0.06, 0.02). The authors did not provide any analysis or discussion regarding whether the interventions had any clinical or practical significance for any of the outcomes. It is also important to note that the authors did not provide any details about how they calculated effect sizes or even which effect size statistic they were reporting. Overall, the reporting of the eligibility criteria and methods used to search, select, and extract data from studies was not clear. Miller and colleagues may have included interventions that encompassed financial literacy, education and access to products and services, but the authors' inclusion criteria were not clear and they did not describe the types of interventions included, aside from referring to them as 'financial education'. Kaiser and Menkhoff (2016) also conducted a review of financial literacy and financial education interventions on financial behaviours.
The authors included 126 impact evaluation studies (published and unpublished) that were designed to impact financial knowledge or behaviours and that report on financial literacy and/or financial behaviour outcomes. 44% of the included studies overlap with the Fernandes et al. (2014) study. 83% of the studies were of classroom financial education, 8% were of online financial education, 2% were individualized counselling interventions, and 7% were informational and behavioural nudges. Results suggest that financial education intervention impacts are less effective for low-income clients and for those in low-and lower-middle income countries. They also found that offering financial education at 'teachable moments' and with increasing educational intensity increases the success of financial education efforts.
Kaiser and Menkhoff (2019) conducted a systematic review and meta-analysis of studies on school financial education programs for children and youth. They built on their existing data set from their 2016 study by using the same search strategy to collect published studies on financial education in school between October 2016 and Sept 2018.
They included 37 studies, 16 of which were new from their previous review. 18 of the 37 studies were RCTs and the others were QEDs.
Their meta-analysis relied on 177 effect size estimates, 70 of which refer to treatment effects on measures for financial knowledge and 107 refer to treatment effects on a set of financial behaviours among students, including credit behaviour, budgeting behaviour, saving and retirement behaviour, and insurance behaviour. They found that financial education programs have, on average, 0.33 standard deviation impact on financial knowledge, which is similar to educational interventions in other domains. They also found a .07 standard deviation impact on financial behaviours among students. The results were robust irrespective of the meta-analytic method used and when accounting for publication bias. The authors find that effect sizes are statistically significant and larger for primary schools as compared to secondary schools, and higher intensity of teaching increases effectiveness. The authors make specific program recommendations for teaching financial education in schools. It should be noted that the reporting of the eligibility criteria was unclear regarding definition of school (i.e., public or private, homeschool, pre-school, etc.). Findings also did not include effect sizes on the various outcomes related to financial behaviour.
While these reviews provide some evidence related to effects of financial capability interventions, serious evidence gaps remain. Fernandes et al. (2014) and Kasier andMankhoff (2016, 2019) included only financial education or literacy efforts without access to a financial product or service. Therefore, the interventions were not designed to increase participant access to appropriate financial products or service that allow them to act on their knowledge. Similarly, Miller and colleagues (2014) appear to have focused on financial literacy interventions. If they included financial capability interventions, they made no distinction between the different types of interventions. In addition to this limitation, the Miller et al. (2014) study also has some shortcomings that limit its usefulness in policy formation. The review had an insufficient search strategy by using a limited number of databases, and therefore the review may have missed potentially relevant studies. The review does not sufficiently describe the types of evidence included in the review and does not assess the risk of bias in the included studies. Thus, these studies do not provide evidence about whether interventions that combine financial literacy with financial products and services are effective.
As interventions to improve financial capability move forward, more evidence is needed about the effects of interventions that combine financial education and financial products and services. It is important that practitioners, policy makers and stakeholders have access to synthesized evidence of the effects of approaches to improve financial capability to make informed decisions, rather than relying on results of individual studies. A systematic review could inform practice decisions by providing evidence about the components of a financial capability intervention that are essential to effect participant financial outcomes. Policy decisions about essential program design elements required for funding could also be guided by evidence.

| OBJECTIVES
The purpose of this review is to inform practice and policy by examining and synthesizing evidence of the effects of interventions designed to improve financial capability. Financial capability interventions combine financial education and financial products and/or services. The following are the research questions for this review: What are the effects of interventions designed to improve financial capability on financial behaviour and financial outcomes?
Does study (design), intervention (dosage, duration, type) or sample (age) characteristics relate to the magnitude of effect size? 4 | METHODS 4.1 | Criteria for considering studies for this review 4.1.1 | Types of interventions While definitions, terms, and practices vary across studies, for purposes of this review, financial capability is defined as 'a consumer's ability to apply financial knowledge and perform desirable financial behaviours to achieve financial well-being' (Xiao & O'Neill, 2014).
Financial capability requires both knowledge and access to a financial product or service. Studies eligible for this review examined the effectiveness of interventions designed to improve financial capability that use a combination of financial education or information, and access to a financial product or service.
To be eligible for this review, the intervention must have included a financial education component and a financial product or service.
To meet the criteria for delivering financial education, interventions must have delivered information about: (1) a variety of general financial concepts and behaviours (such as using a formal education curriculum that covers the time value of money and the importance of keeping financial records), or advice about financial behaviours); (2) a specific financial topic (such as a formal or informal one-time education session about savings, homeownership, or a consumer credit report); (3) a specific product (such as retirement savings accounts or savings accounts that can be used for emergency savings); and/or (4) a specific service, such as the value of pre-purchase homeownership counselling to gain access to low-cost financing.
Information about a specific product or a specific company also met the criteria, such as in the case when employer-based financial education is focused on educating their employees about their retirement plan, and options for investing within their plan. Financial education could have been high-intensity, such as one-on-one delivery, one-on-one tailored delivery, or face-to-face classes, or low intensity, such as flyers, emails, texts, videos, or online delivery.
To meet the criteria for access to a financial product or service, interventions must have facilitated access to one or more of the following: (1) a CDA (used for post-secondary education or training, or another type of asset purchased at age 18 or older); (2) a retirement account through an employer; (3) a 'second chance' checking account (for persons listed in a consumer reporting bureau after having insufficient funds for a check; (4) a matched savings account (to pay debts to build assets); (5) a financial service, such as financial counselling or coaching; (6) a bank account; or (7) an investment vehicle, such as a Saving Bond or Certificate of Deposit (CD); or (8) a home mortgage loan product. Facilitating access includes linking BIRKENMAIER ET AL. | 7 of 54 participants to products or services that are tailored towards the population of participants (such as financially vulnerable populations or employees eligible for employer-provided retirement benefits).
This linking could involve financial counselling or coaching, or occur through another process, such as tax filing. The interventions could also facilitate access by signing participants up for the product or service (such as a savings account), deliver services as part of the intervention (financial counselling or coaching), and/or provide ongoing interpersonal support to make it possible for participants to maintain access to a product or service.
Studies that used multicomponent interventions were included as long as two of the components were financial education or information and access to a financial product or service. Studies that described interventions that provided only financial education, or a myriad of other types of services related to financial education, such as literacy, mentoring, goal-setting, and therapy, or only facilitated access to products and services were excluded from this review.
In our search, we found multiple reports of large longitudinal study projects that included different subsets of the large sample, different time periods (e.g., post-test, 18 months post, 36 months post) or different outcomes reported. We also found duplicate reports of the primary studies, as well as summary reports that spanned the findings of multiple primary and secondary studies. We designated these as secondary reports and extracted data from all reports that were relevant to a particular study/primary report.
Studies conducted in non-OECD countries were excluded for several reasons. First, this limitation assisted in maintaining a reasonable scope to the project, and could produce findings relevant to a large population in the US and other developed countries. Second, the financial system in the US and other developed countries have distinctive features not shared by financial systems in developing countries. The comparison of impact of financial capability interventions may not be justified across financial systems. Studies were also excluded that teach financial education only or only facilitate access to financial products and services.

| Types of participants
Financial and economic policies and practices can be quite different for high-income compared to low-and middle-income countries.
Therefore, the focus of this review was on financial capability interventions in high-income countries. To be included, studies must have been conducted with participants in any of the 35 member countries of the Organisation for Economic Co-Operation and Development (OECD). Studies with participants of all ages were included.

Types of outcomes
Studies must have measured at least one of the following primary outcomes. These outcomes reflected financial behaviour: Behaviour change. Behaviour change refers to changes in financial behaviours of participants, such as opening a savings or checking account, owning a retirement or College Savings account, active use of savings or checking accounts, increased frequency of savings, change from using predatory financial products to mainstream financial products, purchase of an asset, reviewing credit report, etc.
Financial outcomes. Financial outcomes refers to implications of behaviour change, such as higher fund balance in a savings or checking account, higher net worth, lower debt, and improved credit scores.
If studies measured one of the above primary outcomes, data was to be extracted on the adverse effects as a secondary outcome, such as a decrease in material well-being as a result of saving for a child's college education.
Measurement of above outcomes could have been conducted using standardized or unstandardized instruments, and self-or other-reported or researcher administered measures. Thus, the reviewers did not exclude measures based on the type of measure, but planned to pool effects based on type of measure used (e.g., observational measures pooled with observational measures). In the planned meta-analysis, to be included, study authors must have reported enough information to calculate an effect size. If sufficient information to calculate an effect size was not provided, every effort was made to contact study authors and request the necessary information.

| Types of study designs
To mitigate threats to internal validity, studies must have used a prospective randomized controlled trial (RCT) or quasiexperimental (QED) research design with parallel cohorts (the control/comparison group cannot consist of study dropouts).
Studies using single-group pre-post test design (SGPP), or single subject design (SSD), or historical comparisons were excluded.

| Types of comparison conditions
For RCT and QED studies, wait list control, no treatment, treatmentas-usual and alternative treatment groups were considered accep-  (Kugley et al., 2017).
The search strategy and results of the search are documented in a detailed flow chart (Figure 2: Study Screening Process). Table 1 contains the identity of the electronic databases and research registries, and government (e.g., the Consumer Financial Protection Bureau, Federal Reserve Banks) and organizational websites searched for this study. The databases were searched using key terms, as well as the names of specific types of financial capability interventions (e.g., 'Child Development Account' and 'pre-purchase homeownership education').
In addition to databases and organizational websites, research registries and websites, the reference lists from prior reviews (Fernández-Olit et al., 2019;Kasier & Mankhoff, 2016, 2019Miller et al., 2014) and included studies were harvested for potential studies. We conducted forward citation searching using Google Scholar to search for studies citing the included studies. We also conducted a search on Google using key terms. The Google Scholar search included conference proceedings. We hand searched the table of contents of selected journals to identify potentially eligible reports not properly indexed (see Table 1 for more details). Our search for conference proceeding by Google Scholar and hand searching of F I G U R E 2 Study screening process BIRKENMAIER ET AL. | 9 of 54 relevant journals did not find any additional studies from the results of our search of the databases, websites, reference lists of prior reviews, Google Scholar and Google.
Finally, experts who were study or sub-study authors of prior studies were contacted in an attempt to obtain unpublished studies, studies in process and published studies missed in the database search. Contact was attempted with 12 experts (i.e., study authors) through email. Each expert was contacted twice by email with a request for information about unpublished studies, studies in process and published studies missed in the database, as well as missing data.
If there was no response, no further contact was made. No additional unpublished studies were provided by any author from within our time frames (see Table 1 for more details).

Search terms and keywords
We used combinations of terms related to the intervention and study design to search the electronic databases. Database-specific strategies were explored for each database in consultation with a librarian at Saint Louis University, including the use of truncation and database-specific limiters, and thesauri were consulted to employ more precise search strategies within each database. Below are examples of the types of terms we used (see Appendix A for more details about database searches): Intervention: (financial OR economic OR bank) AND (education OR knowledge OR literacy), AND (capability OR access OR inclusion OR exclusion OR attachment) AND Report type: (evaluation OR intervention OR treatment OR outcome OR program OR trial OR experiment OR 'control group' OR 'controlled trial' OR 'quasi-experiment' OR random*) The databases were also searched using the following names of specific types of related interventions: 'Individual Development Accounts', 'Child Development Accounts', 'credit counseling', 'prepurchase' and home OR house, 'second chance' or '2nd chance' and accounts, workplace OR 'employer-sponsored' AND retirement OR savings, and 'financial education'.

| Data extraction and management
Two reviewers independently coded all studies that passed the eligibility screening process described above using a structured data extraction form (see Supporting Information Appendix C). The coders pilot tested the code form together using diverse types of studies and discussed any items that were unclear and ensured mutual understanding of all items. Following pilot testing of the form, the two coders independently coded 100% of the included studies. The coders compared coding and identified and discussed discrepancies, which were resolved through consensus.
Any study coauthored by one of the reviewers was coded by two other reviewers (e.g., Youngmi Kim and Brandy Maynard coded studies that were co-author by Julie Birkenmaier, and vice versa).
Multiple reports on individual studies were collated. The data extraction form included items related to bibliographic information and source descriptors, methods and procedures, context, nature, and implementation of the intervention, sample characteristics, and outcome data needed to calculate effect sizes.

Risk of bias
Three review authors participated in risk of bias assessment. At least two review authors who were not study authors independently assessed risk of bias in all included studies using the Cochrane Collaboration's risk of bias tool (Higgins et al., 2011). The review authors assessed risk of bias for each of the seven following domains: sequence generation, allocation concealment, blinding of participants and personnel for all outcomes, blinding of outcome assessors for all outcomes, incomplete outcome data for all outcomes, selective outcome reporting, and other potential sources of bias (i.e., researcher allegiance, funding source). Each study was coded as 'low', 'high', or 'unclear' risk of bias on each of the domains. Following independent coding by at least two review authors, they met to identify and resolve any discrepancies through consensus. We anticipated that most studies included in this review would be at high risk of bias in terms of allocation and blinding; thus, we did not plan to restrict analyses based on risk of bias in any domain.
Following descriptive analysis, we examined the data to calculate effect sizes and prepare for the meta-analysis. All effect sizes were calculated using the Practical Meta-Analysis Effect Size Calculator (Wilson, n.d.). For continuous outcomes, we used author reported means and standard deviations to calculate the effect size when possible. When means and standard deviations were not reported, we calculated the ES using other data when possible. In one case, dichotomous data were reported (e.g., number of participants who opened or did not open an account) and thus we calculated those effect sizes using a 2 × 2 frequency table and converted to d using the Practical Meta-Analysis Effect Size Calculator. We provided a narrative summary and tables describing the study characteristics and effect sizes (or primary author reported results when we could not calculate an effect size) for each of the outcomes of interest. Effect sizes could not be calculated for some studies due to authors not reporting sufficient information (most commonly, authors not reporting standard deviations). Review authors contacted study authors for missing information and in one case, the author did respond with more data.
As discussed in the Results section, a meta-analysis could not be conducted due to the diversity of types of interventions that did not make sense to pool (e.g., effects of college savings with retirement accounts) and/or a lack of study authors reporting similar outcomes and/or similar time frames. For example, effect sizes were able to be calculated for saving amounts for three studies, but this outcome is measured across three distinct types of interventions. While the studies in this review met the criteria, the included studies reported on interventions that were disparate in terms of the financial product, BIRKENMAIER ET AL.
| 11 of 54 the targeted population, and goals. Thus, we chose to group the interventions in a way that would be more meaningful and useful to practitioners and policy makers; therefore, we decided not to pool effects across these different categories of interventions with different intervention goals (i.e., saving for child's college education, saving for retirement, lowering debt, etc.).

Deviations from the protocol
The review authors followed the protocol  with three deviations: (1) A second round of search and extraction for sources between May 2017 to May 2020 was conducted; (2) effect sizes were not pooled across different types of interventions; and (3) because the studies had larger sample sizes (i.e., all >150), we did not see the need to correct for small sample size bias using Hedges' g as planned.

Criteria for determination of independent findings
The review authors were interested in two primary outcome constructs: behaviour change and change in access to a financial product or service resulting in financial outcome changes. The review authors anticipated that some included studies may use multiple measures for each outcome, multiple reports of the same outcome measure, multiple follow-up time points, more than one intervention, and possibly more than one counterfactual condition. These circumstances create statistical dependencies that violate assumptions of standard metaanalytic methods. To ensure independence of study-level effect sizes, we included only one effect size estimate from each independent sample at each distinct measurement point (e.g., post-test, follow-up).
Although we were not able to conduct a meta-analysis, we were very attentive to ensuring that we were not counting multiple reports as independent included studies. Reports refers to publicly available summary documents of included studies (a total of 63 reports with duplicates and summary reports, and 48 unduplicated reports in this review).
The sub-studies reported on both participant-owned accounts (100%) and state-owned account (67%). Low-intensity financial education was provided in the intervention (100%).
The Michigan SEED Children's Savings Program (MI SEED) was also a randomized control trial, and resulted in two sub-studies families involved with the (federal preschool) Head Start program. As seen in Table 6, the two sub-studies were reported as unpublished reports (100%). The sub-studies were conducted 4 years post-baseline.
The sample size was 600 and 628 for the sub-studies (100%), and only participant-owned accounts were studied (100%). Low-intensity financial education was provided to the participants (100%).
The Parks Opportunity Program, also known as the 'Assessing Financial Capabilities Outcomes Adult Pilot', was a randomized control trial. The study resulted in three sub-studies (Collins & Nafziger, 2019;Gons, 2013;Wiedrich et al., 2014). The intervention targeted employees. As seen in Table 7, one sub-study was reported as an unpublished report (33%), one study was a journal article (33%), and the third as 'other' (presentation) (33%).
The Assets for Independence Program was a randomized control trial. As seen in Table 8, the study resulted in two sub-studies (Mills et al., 2016;Ratcliffe et al., 2019). Both sub-studies were reported as unpublished reports (100%). The sub-studies were conducted at 1 and 3 years post-baseline. The sample size was 621 (k = 1, 50%) and 807 (k = 1, 50%).
Sub-studies. As seen in Table 3, in the nine sub-studies resulting from the American Dream Demonstration Project (ADD) large longitudinal study, the predominant race for the majority of the study projects was White (k = 59, 100%). Study participants were adults who were predominately 34-38 years old (67%). All of the sub-studies had lowincome participants. Most of the sub-studies had a sample of 20% males (67%). None of the sub-studies assessed whether the participants previously had received financial education. projects was White (50%) and not reported (50%). One sub-studies had participants with all incomes, and the other was not reported.

As displayed in
Study participants were predominately 31-41 years old (100%). One sub-study reported that 9%-10% of the participants were male, and the other study did not report gender breakdown. Neither of the substudies assessed whether the participants previously had received financial education.
As seen in Table 7, in the three sub-studies resulting from the Parks Opportunity Program large longitudinal study, the predominant race was African American for two sub-studies (75%) and not reported for the other (25%). Study participants were an average of 36 years old (100%) for all sub-studies. All three of the sub-studies had participants with low-incomes, and the studies had 21%-22% males. None of the sub-studies assessed whether the participants previously had received financial education.
As seen in

| Outcome measures
In the 24 unique studies, data were collected on the outcomes of financial behaviour and financial outcomes of the study participants using unstandardized instruments, and including self-reported and administrative data.  ; and 4 years (MI SEED [Marks et al., 2009]).

Unique studies
In the 24 unique studies, data were collected on financial behaviour and financial outcomes of the study participants using unstandardized instruments, and included self-reported and administrative data. Six of the studies are large longitudinal studies, whose outcomes are reported in the sub-studies (discussed next). As seen in Table 2, together with the remaining 18 studies, five behaviour changes were studied as outcome measures: bank or retirement account opening (k = 7, 29%), retirement saving rate (k = 3, 13%), saving rate (k = 1, 4%), budgeting (k = 2, 8%) and purchased asset (k = 3, 13%). The financial outcomes refer to implications of financial behaviour change. Savings amount (k = 18, 75%), debt amount (k = 5, 21%), credit score (k = 7, 29%), asset value (k = 3, 13%) were studied.
Sub-studies-In the 28 sub-studies of the six large longitudinal studies, data were also collected on financial behaviour and financial outcomes of the study participants using unstandardized instruments, and included self-reported and administrative data. The data are displayed in Tables 3-8. As Table 3 shows, in the nine sub-studies resulting from the American Dream Demonstration Project large longitudinal study, in terms of behaviour outcomes, the majority studied the change of purchased asset (78%), including homeownership (k = 3, 33%), education (k = 1, 11%) and retirement savings (k = 1, 11%). Also studied was retirement savings rate (k = 1, 11%).
Regarding financial outcomes, the largest number of sub-studies focused on asset value (33%), followed closely by debt amount (22%) and saving amount (11%). As seen in Table 4, in the three sub-studies resulting from the Credit Building in Individual Development Account (IDA) Program large longitudinal study, in terms of outcomes, all of the sub-studies assessed financial outcomes of credit score (100%).

| Excluded studies
As seen in Figure

| Risk of bias in included studies
We used the Cochrane Risk of Bias tool (Higgins et al., 2011) that is commonly used to assess risk of bias in experimental studies of intervention effects. Although later versions are available, Campbell has not made a policy to adopt newer versions of the Cochrane Risk of Bias tool.
As seen in Table 9, the risk of bias varied across studies. The majority of the study designs were randomized controlled trials, and the remainder of the studies were quasi-experimental designs with comparison groups.
Because the included studies did not have pre-registered protocols, it is difficult to assess reporting bias for incomplete outcome data for all outcomes or selective outcome reporting. None of the included studies employed blinding of participants or personnel. With a few exceptions, there is a general absence of information related to the study authors' role in the interventions or potential bias stemming from study funding, thus we could not assess potential bias related to researcher allegiance or funding. Few studies had information about allocation concealment or blinding of outcome assessors for all outcomes.
Many studies did not report adequate data for review authors to calculate effect sizes.
Generally, the studies were conducted with randomly selected samples or convenience samples, and large sample sizes, and thus findings were generalizable. All study authors recognized study limitations and recommended that research on intervention effectiveness continue and that more rigorous research be conducted.

| Study intervention, design and outcomes by financial capability intervention strategy
As seen in Table 10, effects sizes and author-reported outcomes or effect sizes varied across studies. The studies are reported here grouped by type of program (e.g., Matched Savings Accounts) and reported in yearly ascending order. Savings for Success' program), all of which are described below. In addition, an unrelated matched savings account study (Leckie et al., 2010a) is also discussed in this section.  , 2012, 2013a, 2013bHan et al., 2009;Huang, 2010;Lombe, 2004;Mills et al., 2006) all used data from the Tulsa Oklahoma site, which was the only site that used a randomized control trial research design. The studies used various data sources, time frames, and sub-samples from the total sample of n = 2350 to examine a variety of financial outcomes, including savings amounts and asset value, and behavioural outcomes including account opening, saving rates, and asset purchase.

ADD
For all studies/reports of the ADD project discussed below, the role of the evaluator was completely independent from the treatment; non-profit staff members delivered the intervention after training through periodic contact with participants. The number of contacts and whether the intervention was manualized was not re-  For all of these studies, the risk of bias is high for incomplete outcome data for all outcomes (because both the treatment and control groups had high attrition (over 20% reported) and other biases (researcher or funding bias) because an author designed the intervention. Risk of bias is unclear for sequence generation, blinding of participants and personnel, selective outcome reporting, and judged as low for blinding of outcome assessors, and allocation concealment.
The studies are reported from the earliest to the most recent studies.
Lombe (2004)        Account Opening (4 to 11 months post) The study authors reported that the intervention increased account opening by 6%, and the rate of creation of a budget by almost 6%.
The intervention increased the retirement savings participation by 3.7%-3.8%, the retirement savings rate by 40.4%, and emergency savings by 3.8% Budgeting ( Debt (6 and 12 months post) Study authors report that the intervention led to 13% reduction in past debt due over a 12-month period for the treatment group Saving Amount (6 and 12 months post) For the outcome of savings amount, the treatment group experienced reduced bank balances in the 6-12 month post-intervention period, which was not statistically significant. Post-intervention, the mean bank balance for the treatment group was $41 less  Kim, Garman, Sorhaindo Credit Score (6 months post) For credit score outcomes, study authors report that the mean of the treatment group post-intervention was 702.42 and 703.7 for the control group. For the debt outcome, study authors report that the mean debt for the treatment group was $4926, and $5118 for the control group Debt (6 months post) Roder (2016) Roder (2016) Credit score (2 years post) The study authors report a Hedges g effect size of 0.01. The study author did not report the confidence intervals or sufficient information for the review authors to calculate an effect size T A B L E 1 0 (Continued) (i.e., education level, children under age 17, marital status, race, and welfare status) and participated in three waves of data collection.
Substantial attrition was observed between the time the original sample was recruited and the wave of data collected that was used for this study due to dropout or missing data at wave III. The mean age of participants was 36.5 years, with 17% of the participants being male. Using interview, survey, and administrative data, Lombe evaluated the extent to which treatment group participants purchased an asset and the value of the assets. There was a small but not a statistically significant effect of the intervention on purchase of an asset (i.e., homeownership) (d = 0.11, 95% CI = −0.05 to 0.27) at 4 years post-enrolment. The study author measured asset value, but did not report sufficient data to calculate an effect size. The study is assessed as unclear for bias for substantial attrition. The mean age of participants was 36.3 years, with 20% of the participants being male. The smaller sample size at the 18 months and 4 years post enrolment was due to attrition (drop out and missing data).
They found small, but non-statistically significant effects on purchased assets (d = 0.06, 95% CI = −0.09 to 0.21). Of note is that the study authors examined demographic differences between groups and found statistically significant differences between the treatment and control groups on demographics. Given the substantial attrition and differences in demographics between groups, the review authors judged this study to be at high risk of bias. The sample included only subjects that completed wave III data and were renters at baseline. Control group members received nothing, but were also not barred from receiving homeownership counselling from other area providers besides the intervention provider. The  did not report sufficient information. Study authors reported a mean of $4332 for the treatment group saving amount (n = 311) and a mean of $5756 (n = 340) for the control group. It must be noted that the study authors did examine demographic differences between groups and found statistically significant differences on demographics between the treatment and control groups. Given the differences between groups on demographics and the high attrition between the original study enrolment and the sample sizes used for analysis of these outcomes at 10 years post-enrolment, risk of bias was judged as high for these studies/outcomes.

Assets for Independence (also known as 'Building Saving for Success')
Assets for Independence is a longitudinal study of the Individual Development Accounts (IDA) intervention implemented in two community-based sites: at a community college in Albuquerque New

Mexico and a community-based nonprofit organization in Los Angles
California. Participants received high-intensity (face-to-face) financial education classes and a matched savings account to help build financial assets. Participants could use their matched savings to purchase an asset, such as a home, a vehicle, or post-secondary education. Treatment group participants were offered a match (i.e., participant savings were matched with incentive funds (i.e., money from the program). One site offered a match of 4-to-1, and the second offered a 2.5-to-1 match.
Researchers used an experimental design to study financial out- Whether treatment or control group had high attrition was unreported.
Study authors reported saving amount and purchase asset outcomes 3 years post-baseline. For saving amount, a small but not statistically significant effect was found for liquid assets amount (d = 0.18, 95% CI = −0.05 to 0.41). A small but not statistically significant effect was found on asset ownership (d = 0.10, 95% CI = −0.12 to 0.33).

Credit Building in Individual Development Account (IDA) Programs
The second large study about matched saving accounts is the 'Credit For all studies discussed below, the unit of assignment to condition was individual. The treatment and comparison groups were not matched. High-intensity (face-to-face, classroom-based, multiple session) financial education was delivered in the intervention. The predominant race of participants was African American, and the mean age was 31-40 years old. The role of the evaluator was independent from the treatment; the non-profit staff delivered the intervention through periodic contact with participants. Whether the intervention was manualized or fidelity was assessed was not reported. Neither the treatment nor the control group had high attrition (under 20% reported). The control group received nothing during the intervention. The three studies (Birkenmaier et al., 2012(Birkenmaier et al., , 2014a(Birkenmaier et al., , 2014b) used the same sample and studied the same outcome (financial credit score) using the same measure (the individual consumer credit report) at three different time periods.
Overall, the risk of bias is high for these studies for sequence generation and unclear for allocation concealment, and blinding of participants and personnel. The risk of bias is low for blinding of outcome assessors, incomplete outcome data, selective outcome reporting, and other (i.e., researcher or funding allegiance bias).
The first sub-study, Birkenmaier et al. (2012), measured out- In the third sub-study, Birkenmaier et al. (2014a) measured outcomes 3 years after baseline measure on the treatment (n = 79) and comparison groups (n = 85), for a total sample of n = 164. The study authors did not compare pre-test differences on outcomes or demographics. Thirteen percent of the sample was reported as male.
We could not calculate the effect size for savings amount or credit score, as the study authors did not report sufficient information. The study authors reported that results of the Wilcoxon Signed Rank Test indicated that the treatment group had significant increases in their median credit score between the first and last wave (z = −3.05, p < 0.05). The median score increased 30 points. The control group also had statistically significant increases overall (z = −2.03, p < 0.05), with a median increase of 21 points. In this study, the full sample was 790, and they experienced 14% attrition from baseline. The sample was further reduced by respondents who did not provide outcomes measure data. The separate attrition rates of the treatment and control group were not reported. No statistical pre-test comparisons were made on differences in outcomes, and no statistically significant pre-test differences on demographics were found. The mean age of the parent participants was 30 years old. The predominant race of the participants was not reported, nor was the gender distribution. The role of the evaluator was not reported. The frequency of contact was not reported.
Using baseline and follow-up survey data, they analysed account opening and saving amounts of participants. The effects of the intervention on account opening were large and statistically significant BIRKENMAIER ET AL.
| 39 of 54 (d = 1.708, 95% CI = 1.446 to 1.969); treatment participants opened more savings accounts than the control group. We could not calculate the effect size for savings amount, as the study authors did not report sufficient information. The study authors report that the mean savings in the treatment group was $912 (n = 302), and $288 (n = 298) for the control group.

SEED OK
The were also used. Control group infants (n = 1346) and mothers received nothing, but were not barred from opening an individual OK 529 account.
The predominant race of participants was White. Participants were all income levels. The sub-study authors also served as the evaluator because the study authors delivered the mailed financial education materials and arranged for the state to provide birth records and open accounts. Periodic contact was made with the participants. Whether the intervention was manualized or fidelity was assessed was not reported. Neither the treatment nor the control group had high attrition (under 20% reported). Unless otherwise noted, the treatment and comparison group were not matched.
The following nine sub-studies (Beverly et al., 2014;Huang et al., 2013;Clancy et al., 2016;Huang et al., 2017;Huang et al., 2019; used various research methods, time frames, types of 529 accounts, and populations within the n = 2704 total sample to study the financial outcome of savings amounts and behavioural outcome of account opening from participants participating in this study. Overall, risk of bias was assessed as low for these studies in bias domains of sequence generation, allocation concealment, and blinding of outcome assessors. The risk of bias was assessed to be unclear for blinding of participants and personnel, incomplete outcome data, selective outcome reporting and other. Because some sub-studies selected sub-samples, some bias may be introduced, depending on how those subsamples were selected. Huang et al. (2013) examined effects at 3 years post-baseline for participant-owned accounts. Their sample included n = 2675 (n = 1341 treatment group, and n = 1334 control group) participants.
In this study, no statistical pre-test differences were found on outcomes or demographics. The mean age of the parent participants was 26, and the mean age of the infants was not reported, although the infants would have been around the age of three at the time of this study. About half (53.13%) of the children were male. Using administrative data and baseline telephone survey, they analysed the ex- participants. In this study, no statistical pre-test differences were found on outcomes or demographics. The mean age of the parent participants was 25-34 years old, and the mean age of the infants was not reported, although the infants would have been around the age of 18 months. About half (53.09%) of the children were male.
Using administrative data and baseline telephone survey, they ana- The percentage of the participants who were male was not reported.
In this study, no statistical pre-test differences were found on outcomes or demographics. The mean age of participants was not reported, although the infant participants would have been around the age of 2-3 years old. Using interview and telephone survey data, they analysed data on participant-owned and state-owned account opening and saving amount. We could not calculate the effect size of the intervention on participant-owned account opening because they were combined with state-owned account opening, which was part of the intervention. We could not calculate the effect size for savings amount, as the study authors did not report sufficient information.
Study authors reported that the mean savings for the treatment group was $1130 (n = 1358) and the mean savings for the control group was $75.7 (n = 1346).
Beverly  studied n = 2698 (n = 1353 treatment group, and n = 1345 control group) at 3 years post-baseline for participant-owned and state-owned accounts. In this study, no statistical pre-test comparison was made on outcomes, and no statistically significant differences on pre-test demographics were found. The mean age and gender of participants were not reported, although the infant participants would have been between 2 and 3 years old at the time of the study. Using telephone survey and interview data, they analysed account opening and savings amounts for all accounts. We could not calculate the effect size of the intervention on participant-owned account opening because they were combined with state-owned account opening, which was part of the intervention. We could not calculate the effect size for savings amount, as the study authors did not report sufficient information.
The study authors reported that the mean saving amount for the treatment group was $1129.85 (n = 1353) and the mean saving amount for the control group was $75.74 (n = 1345). participants. In this study, no statistical pre-test comparison was made on outcomes, and no statistically significant pre-test differences on demographics were found. The mean age of the parent participants was 25.5 years old, and the mean age of the infants was not reported, although the infants would have been around the age of six. About half (52.48%) of the children were male. Using baseline telephone survey and administrative data, they analysed account opening for participant-owned accounts, savings amount for participant-owned accounts, and asset value. The effects of the intervention on account opening were large (d = 1.63, 95% CI = 1.33 to 1.93). We could not calculate the effect size for savings amount or asset value, as the study authors did not report sufficient information.
The study authors reported that the mean saving amount for the treatment group was $153.71 (n = 1358) and the mean saving amount for the control group was $31.96 (n = 1346). The study authors reported that the mean asset value for the treatment group was $1605.07 (n = 1358), while the mean asset value for the control group was $50 (n = 1346).  examined effects at 5 years post-baseline for participant-owned accounts. Their sample included n = 2626 (n = 1318 treatment group, and n = 1308 control group) participants at 4-5 years after baseline telephone interview survey. In this study, no statistical pre-test comparison was made on outcomes and statistically significant pre-test differences on demographics were found. The mean age of the parent participants was 25.57 years old, and the mean age of the infants was 39 months. About half (53.1%) of the children were male. Using administrative data and baseline telephone survey data, they analysed the extent to which participants participants. In this study, no statistical pre-test comparison was made on outcomes, and statistically significant differences on pre-test demographics were found. The mean age of the parent participants was 25.6 years old, and the mean age of the infants was not reported, although the infants would have been around the age of seven. The gender of participants was not reported either. Using telephone interview, survey, and administrative data, they analysed account opening and savings amount for state-owned and participant-owned accounts. We could not calculate the effect size of the intervention on participant-owned account opening because they were combined with state-owned account opening, which was part of the intervention. We could not calculate the effect size for savings amount, as the study authors did not report sufficient information.
The study authors reported that the mean saving amount for the treatment group was $1,851 (n = 1358) and the mean saving amount for the control group was $322.8 (n = 1346). In this study, no statistical pre-test comparisons were made on outcomes or found on demographics. In this study, the treatment and control group were matched based on demographics. The mean age of the parent participants was 20-29 years old, and the mean age of the infants was not reported, although the infants would have been around the age of five at the time of this study. The percentage of the children that were male was not reported. Using administrative data and baseline telephone survey, they analysed savings amounts and the extent to which participants opened participant. The effects of the intervention on participant account opening were large (d = 1.62, 95% CI = 1.31 to 1.92). We could not calculate the effect size for savings amount, as the study authors did not report sufficient information. The study authors reported that the mean saving amount for the treatment group was $152.93 (n = 1343) and the mean saving amount for the control group was $32.18 (n = 1334). (TANF) and/or Head Start. They studied participant-owned accounts in the study. Study authors used a follow-up survey and administrative records to study outcomes at 4 years postintervention, which was 7 years after baseline. In this study, no statistical pre-test comparison was made on outcomes, and no statistically significant differences on pre-test demographics were found. The mean age of the parent participants was 24 years old, and the mean age of the infants was not reported, although the infants would have been around the age of seven. The predominant race was White. 55% of the children were male, and all of the parents were female. Neither the treatment nor the control group had high attrition. Study authors reported opening account and asset value outcomes at 4 years post-intervention, which was also 7 years after baseline. For participant-owned accounts, a small significant effect size was found (d = 1.524, 95% CI = 0.149 to 2.898). A small significant effect size was also found for asset value (d = 3.153, 95% CI = 2.868 to 3.437). The majority of the treatment group were from 'economically disadvantaged families', but the income level of treatment or comparison group participants was not specified. Students in both groups took a pre-test before beginning financial education and a post-test 1 week after financial education concluded. Deposits up to $50 were matched one-to-one for the treatment group. Researchers collected pre-test and post-test data on financial education, administrative data from the financial institution and school, and conducted focus groups and interviews. The method of assignment of schools (and participants within the schools) to condition was not reported. In this study, statistical pre-test comparisons were not made on differences in outcomes or demographics. The treatment and control groups were not matched. The mean age of the participants was 9-10 years old.
The percent of the sample that was male was not reported. The predominant race of the participants was Hispanic. School officials and bank representatives delivered the intervention. The role of the evaluator was not reported. The frequency of contact was three times per week for 10 weeks (for the financial education). The attrition for both the treatment and control group was not high (under 20%). The study authors did not report whether the intervention was manualized, or whether fidelity was assessed.
Overall, the risk of bias is high for this study for sequence generation. The risk of bias is unclear for allocation concealment, blinding of participants and personnel, selective outcome reporting, and other.
The risk of bias is low for blinding of outcome assessors and incomplete outcome data. Using administrative data, study authors analysed account opening and savings amounts. The total sample was n = 393 (treatment group n = 196, control group n = 197). Study authors did not report account opening or saving amounts for the control group, thus, effect sizes could not be calculated. Study authors report that 13.8% of the treatment group opened accounts, and the mean savings for the treatment group was $135.06. In this study, statistical pre-test comparisons were not made on differences in outcomes, but statistically significant pre-test differences on demographics were found. The treatment and control groups were not matched. The mean age of the participants was 16-21 years old. 44.5% of the sample was male. The predominant race of the participants was Asian, and 66.5% of the subjects had received financial education previous to the intervention. Non-profit staff delivered the intervention. The role of the evaluator was separate from the delivery of the intervention. The frequency of contact was periodic. The attrition rate for both the treatment and control group, the number of sessions, whether the treatment was manualized and whether fidelity was assessed were not reported.

| Youth
Using pre-test and post-test survey data and administrative data, the study authors evaluated saving amount at the end of treatment, but reported for the treatment groups only, thus we cannot calculate an effect size. Study authors reported that 97% of the youth in the treatment groups established a savings account and 96% met their savings goal. All of the participants in the treatment group saved some portion of their income, with total savings ranging from $9 to $2,268. Overall, the risk of bias is high for this study for sequence generation and other (research allegiance confounds). The risk of bias is unclear for allocation concealment, blinding of participants and personnel, incomplete outcome data, and selective outcome reporting. The risk of bias is low for blinding of outcome assessors. The risk of bias is also high because only outcomes for treatment groups are reported. Duflo et al. (2006) analysed a randomized control trial of a retirement account intervention with tax filers in St Louis, Missouri (US) who used the private company H&R Block as paid tax preparers during 1 month of tax-season. Participants were all tax filers of any income using the service during the 1-month intervention period, and were individually randomly assigned to the treatment or control group.

| Retirement Accounts
While participants were physically at the tax preparation office, tax preparers delivered low-intensity financial education (brief, face-toface, only related to their taxes and retirement savings), along with matches of 20% (treatment group 1) and 50% (treatment group 2) of participant contributions into the self-retirement funds (IRAs) from the amount of money refunded to them through their tax returns.
The control group received no financial education and zero match.
In this study, statistical pre-test comparisons were not made on differences in outcomes or demographics. The treatment and control groups were not matched. The mean age of the participants was not reported. The predominant race of the participants or gender of participants was not reported. The role of the evaluator was separate from the treatment. The frequency of contact was once, for just one session. The attrition for both the treatment and control group was less than 20%. The study authors did not report whether the treatment was manualized or fidelity assessed. The review authors assessed the risk of bias to be low for bias domains of sequence generation, incomplete outcome data, and blinding of outcome as-  Statistical pre-test comparisons were not made on differences in outcomes or demographics. The treatment and comparison groups were not matched. The mean age of the parent participants was not reported. The predominant race of the participants and gender of participants was not reported. University staff delivered the intervention. The role of the evaluator was not independent of the treatment. The attrition rate for both the treatment and control group was not reported. Study authors did not report whether the treatment was manualized or fidelity was assessed.
Using posttest survey data, study authors studied the outcomes of account opening.
The study authors did not include data needed to calculate an effect size for account opening. Study authors reported that the intervention resulted in a 56.2% increase in account opening within 30 days of the intervention compared to the comparison group. The review authors noted that the risk of bias is high for this study for sequence generation, and other (research allegiance), and unclear for allocation concealment.
The risk of bias is also unclear for blinding of participants and personnel, incomplete outcome data, and selective outcome reporting. The risk of bias is low for blinding of outcome assessors. Statistical pre-test comparisons were not made on differences in outcomes, but statistically significant differences were found on demographics. The treatment and comparison groups were not matched. The mean age of the parent participants was not reported. The predominant race of the participants was white. 19% of the participants were male. All income levels were included in the groups. The intervention setting was the credit union, and the staff delivered the intervention. The role of the evaluator was separate from the treatment. Neither the frequency of contact nor the length of sessions was reported. The attrition for both the treatment and control group was not reported and could not be calculated. It was not reported whether the treatment was manualized or fidelity was assessed. We were unable to report effect sizes with the data provided.
The study authors reported that the intervention increased account opening by 6%, and the rate of creation of a budget by almost 6% more than the comparison group. The intervention increased the retirement savings participation by 3.7%-3.8%, the retirement savings rate by 40.4%, and emergency savings by 3.8% as compared to the comparison group. The risk of bias is high for this study for se- In this study, the length of treatment was not reported. Nonprofit staff members delivered the intervention at a community based non-profit organization. Staff had periodic contact with treatment subjects, but the number of sessions was not reported. The intervention was evaluated 5 years after baseline measurement. Statistical pre-test comparisons were not made on differences in outcomes, and no statistically significant differences were found on demographics.
The treatment and comparison groups were matched using propensity score matching. The mean age of the parent participants was 25-34 years old. The predominant race of the participants was African American. 32.3% of the sample was male. All income levels were included. The role of the evaluator was independent of the treatment. The intervention was manualized, and fidelity was assessed. However, the method by which fidelity was assessed was not reported. Both the treatment and control group had high attrition (more than 20%).
Using baseline and annual surveys, paired with administrative data, the study authors studied credit scores, saving amount and debt unable to open one, often due to their name appearing on a consumer debt registry. In this study, statistical pre-test comparisons were not made on differences in outcomes or demographics. Gons and colleagues evaluated the outcomes of debt and credit scores at 9 months post-treatment. The study author did not report sufficient information to calculate effect sizes for any of the outcomes of interest for this review. The study author reports that study participants had 'better outcomes with respect to credit scores, lower levels of revolving debt and fewer accounts in collections than those who did not receive financial counselling'. The risk of bias from sequence generation is low. ported credit scores at 6 and 12 months post-intervention. Study authors report that in the first 6 months post-intervention, the treatment groups experience 'some increase' in credit scores. However, during the 6-12-month period, the control group also experienced increased in credit scores and caught up to the treatment group. At the 12-month mark, there was no measurable effect of counselling on credit scores. The study authors also reported Study authors report that the intervention led to 13% reduction in past debt due over a 12-month period for the treatment group. For the outcome of savings amount, the treatment group experienced reduced bank balances in the 6-12-month post-intervention period, which was not statistically significant. Post-intervention, the mean bank balance for the treatment group was $41 less.  received an online individualized financial assessment, low-touch (online) financial education that involved budgeting and goal-setting before their mortgage loan closure, and individualized post-purchase financial coaching delivered quarterly by a non-profit organization.
Participants were individually randomly assigned to groups. No pretest statistically significant differences were found on outcomes or demographics. The groups were not matched. Control group participants (n = 130; total n = 425) received the online financial education only. Researchers and OHFA staff designed the intervention, and researchers trained the non-profit staff who delivered the financial coaching. The intervention lasted 12 months, and was manualized.
The number of sessions or whether fidelity was measured was not reported. Only the treatment group had high attrition (more than 20%).
Using administrative records, a follow-up survey and credit report records, study authors found that the mean age of the participants was 33 years old. The participant predominant race was White, and 54% of their sample were male. The study authors measured saving amount and credit scores at 12 months post-intervention.
Effects sizes were small and not significant for savings amount one-on-one (high-intensity) financial education and coaching, and financial access was also offered to participants. The treatment group (n = 500) were those participants who received financial education and supported access to financial products/services from the nonprofit agencies. The comparison group (n = 649) were subjects who received employment and training only from public (city) workforce centres (total sample n = 1149). The length of treatment was 6 months to 3 years.
Non-profit staff in the non-profit setting delivered the intervention. The treatment and comparison groups were matched using propensity score matching based on employment experience, demographics and financial situation. After matching, statistical pre-test comparisons did not find differences on outcomes or demographics.
The mean age of the participants was 38 years old. The predominant race of the participants was African American and 45% of the sample was male. Participants were low-and moderate-income. The role of the evaluator was independent of the intervention. The frequency of contact was periodic, with a mean of nine sessions. The study authors did not report whether the intervention was manualized, and fidelity was not assessed. Both the treatment and control group had high attrition (more than 20%).
Outcomes were measured at 2 years post treatment. Using phone surveys, credit reports, administrative data, program observations and staff interviews, study author studied the outcome of credit scores. The effect of the intervention on credit scores is trivial.
The study authors report a Hedges g effect size of 0.01. The study author did not report the confidence intervals or sufficient informa- Control group participants (n = 150; total n = 300) received no services.
Both the treatment and control group received financial incentives to participate in the study for 1 year. Non-profit staff delivered the intervention on the work site, and the evaluators were independent of the intervention. The intervention lasted 18 months. The frequency of the contact, number of sessions, whether the intervention was manualized, or whether fidelity was measured was not reported. Both the treatment and control group had high attrition (more than 20%).
Using credit report and pre-and post-intervention survey data, study authors found that the mean age of the participants was 23 years old. The participant predominant race was African American, and the gender distribution was not reported. The study authors measured credit scores at 18 months post-intervention.
Authors did not provide sufficient data to calculate effect sizes.
Study authors reported significant increase in credit scores among those who initially had a credit file at baseline compared to the control group. The review authors found that the risk of bias is high for incomplete outcome data. The risk of bias is low for sequence generation and blinding of outcome assessors. The risk of bias is unknown for other (research allegiance), allocation concealment, selective outcome reporting, and blinding of participants and personnel.

| Tax refund saving and investment
Refund to savings was n = 95,669, and the control group was n = 11,963 (total n = 107,632). No pre-test statistically significant differences were measured on outcomes, but differences were found on demographics (i.e., marital status) that were controlled for in the study. The mean age of the sample, predominant race, nor the gender balance were reported. Study authors reported saving amount outcome. Authors did not provide sufficient data to calculate effect sizes. Authors reported that the treatment groups saved significantly more than the control group. Roll et al. (2018) report on 2016 data, which were collected from mid-January through early June, 2016 (approximately 5 months). The treatment group was n = 70,978, and the control group was n = 213,147, for a total n = 284,125. No pre-test statistically significant differences were measured on outcomes or demographics.
The mean age of the sample was 35.3 and the predominant race was White. The gender balance was not reported. Study authors reported saving amount outcome. Authors did not provide sufficient data to calculate effect sizes. Study authors reported finding statistically significant differences between treatment and control groups on rate of depositing any refund and savings dollar amounts.
Other tax refund study (Tufano, 2011) Tufano (2011)  offices in Illinois were treatment sites, and four offices in Boston were control group sites. Commercial tax preparation staff provided the intervention, and the evaluator was independent of delivering the intervention. There was only one session in the intervention, which was manualized and fidelity was measured through administrative records.
The treatment group (n = 3730) were tax filer customers who learned that they were receiving a tax refund, and were educated about (i.e., low-touch financial education) and provided an opportunity to purchase a US Saving Bond with their tax refund funds. The control group (n = 1484; total n = 5214) received the typical tax filing services without an offer to purchase a savings bond with their refund funds. The groups were not matched. Pre-test statistically significant differences were found on outcomes (i.e., plan to save their refund) and on demographics (e.g., gender and homeownership).
Statistical controls were used to control for these differences. Neither the treatment nor the control group had high attrition.
Using survey data for both the treatment and control group and administrative data, study authors reported that the sample consisted of all incomes. Mean age, predominant race, and gender balance was not reported. The study author reported saving amount and purchase asset outcomes, generated upon completion of filing the tax return.
The study author did not provide sufficient data to calculate effect sizes. For saving amount, study authors report that treatment group members saved an average of $28.21, compared to a control group mean of $12.95. For purchase asset outcomes, study author report that 7% of treatment participants purchased an asset compared to 0.74% of control group participants. The review authors found that the risk of bias is high for this study for sequence generation (quasiexperimental design), and allocation concealment (group assignment was based on site). The risk of bias is low for blinding of outcome assessors, incomplete outcome data, and other (research allegiance, funding, etc.). The risk of bias for blinding of participants and personnel and selective outcome reporting is unknown. The largest category of studies related to financial education, counselling and coaching, followed closely by tax refund saving and investment, retirement, and matched savings accounts for adults. The studies also included CDAs, youth bank accounts, and homeownership education.
Overall, the evidence of the effects of financial capability interventions on financial behaviour and financial outcomes is sparse, given the lack of standardization of outcomes studied, measurement of the outcomes, or timing of measurement. Moreover, there were either only one or very few studies that examined effects of similar types of interventions on similar outcomes, thus we were not able to pool effects of studies to conduct a meta-analysis. We were unable to calculate the effect sizes for the majority of the outcomes in the studies. For those we were able to calculate, effect sizes varied from small to moderate to large. The vast majority of large effect sizes were on account opening outcomes, with a few studies able to demonstrate large effects for saving amount, budgeting, and lowering debt. The studies with large effect sizes for account opening and saving amounts were CDAs and retirement account studies, while one debt management intervention resulted in large effect sizes for budgeting and lowering debt.
The studies that are available have important strengths. The majority of the studies are RCT's (k = 17) and many examine outcomes across several years. While many of the primary studies were RCTs, several of the sub-studies used subsamples, thus those substudies may introduce additional bias depending on how those subsamples were selected.
The risk of bias varies across studies. In addition, a number of the studies were assessed as high risk of bias for attrition and comparison groups differing on important demographic characteristics. Because the included studies did not have pre-registered protocols, it is difficult to assess reporting bias for incomplete outcome data for all outcomes or selective outcome reporting. There is a general absence of information related to the blinding of participants or personnel, as well as other indicators of bias.
While the number and quality of studies included in this review precludes providing a clear answer on the effects of financial capability interventions, this review provides a good indicator of the state of the evidence for financial capability interventions and identified several important gaps to inform future research.

| Overall completeness and applicability of evidence
While the evidence for each type of financial capability intervention indicates effectiveness of the intervention, the evidence across the studies on the effectiveness of financial capability interventions is incomplete.
While the majority of the studies used random assignment (72%), many of the studies had some important methodological weakness.
For example, the majority of studies did not use a manualized intervention or study fidelity. Many of the studies experienced high attrition (more than 20%) in the control and treatment groups.
Many of the studies had a high risk of bias on most items. Because the included studies did not have pre-registered protocols, it is difficult to assess reporting bias for incomplete outcome data for all outcomes or selective outcome reporting. Few of the included studies reported employed blinding of participants or personnel. With a few exceptions, there is a general absence of information related to the study authors' role in the interventions or potential bias stemming from study funding, thus we could not assess potential bias related to researcher allegiance or funding. Few studies had information about allocation concealment, or blinding of outcome assessors for all outcomes.
This review identified several different types of previously evaluated financial capability interventions. Unfortunately, few interventions were evaluated by more than one study that measured the same or similar outcomes, thus there were not a sufficient number of studies of any of the included intervention types that could be pooled to conduct a meta-analysis. Therefore, evidence is sparse about whether participants' financial behaviours and/or financial outcomes are improved after receiving an intervention that met criteria for this review.
6.2.1 | Quality of the evidence While the majority of the studies used random assignment (71%), many of the studies had some important methodological weakness.
For example, the majority of studies did not use a manualized intervention or examine fidelity. We did not find protocols for the included studies, few of the included studies reported using blinding, and the majority did not report on allocation concealment nor on the researchers' roles in intervention development or implementation. Several of the studies experienced high attrition (more than 20%) in the control and treatment groups. Few assessed whether treatment or control group participants previously had financial education. Several large longitudinal studies also assessed outcomes on subgroups taken post-hoc from the full sample, thus compromising random assignment.

| Limitations and potential biases in the review process
The conduct and reporting of this review were guided by Campbell's standards and policies for the conduct and reporting of systematic reviews to ensure a rigorous and transparent review designed to minimize bias and error. This review is not without its limitations, however, and the findings must be interpreted in light of the study's limitations. We made every attempt to search for published and un-

| Agreements and disagreements with other studies or reviews
This is the first systematic review of financial capability interventions that include both financial education and access to a financial product or service. Therefore, we are unable to comment on the degree to which this review agrees with similar reviews or studies.

| Implications for research
While these interventions, the combination of providing a financial product along with education, have good intentions and would seem to be more effective than providing either individually, the evidence to date on the effectiveness of financial capability interventions is sparse and relatively weak. While many of these studies are large longitudinal studies with larger sample sizes, several of them lack the rigour and reporting of necessary information and data to be useful for informing the evidence base. Moreover, many of these large longitudinal studies are reported in multiple reports or sub-studies, thus giving the impression that the evidence-base is larger than it actually is. This body of research could be improved and more useful for informing practitioners and policy makers with some additional methodological and reporting rigour. Specifically, the publishing of protocols would provide additional accountability and rigor to the studies, and reporting all outcomes with sufficient data would allow for greater transparency and greater likelihood in results being able to be pooled in metaanalysis. Developing a common set of outcomes that could be measured and reported across all studies examining effects of financial capability interventions could also assist in building and synthesizing the evidence on financial capability interventions.

ROLES AND RESPONSIBILITIES
Please give brief description of content and methodological expertise within the review team. The recommended optimal review team composition includes at least one person on the review team who has content expertise, at least one person who has methodological expertise and at least one person who has statistical expertise. It is also recommended to have one person with information retrieval expertise:

SOURCES OF SUPPORT
This review had no source of financial support.

DECLARATIONS OF INTEREST
Two of the review authors (Julie Birkenmaier and Youmgi Kim) are also co-authors of some included studies. These authors did not extract data, code data, or critically appraise data from any study which they co-authored. Further, the authors have no vested interest in the interventions or outcomes of this review, nor any incentive to represent findings in a biased manner.

PLANS FOR UPDATING THE REVIEW
The review authors will examine the financial capability literature every 5 years to determine whether this review needs updating.

DATA AND ANALYSES
None.